This invention relates to the chemical processing of coal by utilizing gaseous plasmas. The final products of this processing are organic gases and compounds. The present invention is especially useful to produce high BTU gas such as methane, ethane, ethylene, and propene, for general purpose use at costs lower than those currently required for such gas production, and to produce acetylene, olefins, and other hydrocarbons at low costs.
In recent years, a great deal of work has been devoted to utilizing plasmas in chemical reactions. The utilization of plasmas to produce acetylenes from coal has been attempted. The techniques which have been tried include the use of microwave plasma discharges of hydrogen, radio frequency plasma discharges of hydrogen, and arc discharges of hydrogen to promote a reaction between the hydrogen gas and coal. The reason for utilizing a plasma lies with the high degree of reactivity which is associated with certain hydrogen species that are found in plasmas of hydrogen. In general, the techniques which have been used require elaborate equipment and too much power input in terms of the electrical power required to generate the plasma to justify a process scale-up to an industrial application.
A method of plasma processing which has been used to produce acetylene has been developed under the direction of Dr. Val Krukonis at AVCO in Lowell, Massachusetts, for the Office of Coal Research. In this method powdered coal is ejected into a hydrogen arc. The reactions which take place produce an output gas comprising approximately 11% acetylene, 80% hydrogen, and a variety of minor constituents. The process is said to use only the high temperatures associated with the hydrogen plasmas.
The present invention takes advantage of chemical species of hydrogen which are found in hydrogen plasmas. In particular, H.sub.3.sup.+ is a metastable hydrogen molecule found in plasmas in the pressure regime of 10-100 mm of mercury. It has associated with it approximately 240 Kcal/mole thermodynamic energy more than the H.sub.2 molecule. It also has a charge associated with it. Because of the thermodynamic energy, reactions can be made to occur at lower temperatures than would be possible with molecular H.sub.2. Because of the charge associated with it, it is possible to utilize electric and magnetic fields to direct these species to the coal to be processed.
The ionic processes involved in producing metastable H.sub.3 .sup.+ include the following reactions. ##STR1## Thermodynamically, H.sub.3 .sup.+ has associated with it 239.8 Kcal/mole, and H, atomic, has associated with it approximately 105 Kcal/mole. Because of the definition of thermodynamic free energy, these associated energies related to the active hydrogen species tend to promote reactions.
In the case of H.sub.3 .sup.+ it is possible to use the Lorentz Force Concept [F = q (V .times. B + .epsilon.)] to direct the motion of the charged species in a manner to cause collisions with the materials to be processed.
Finally, the Gibbs magnetic free energy function and the Gibbs electric free energy function contribute to the thermodynamic considerations for a chemical reaction.
As a consequence of the fundamental considerations noted, favorable yields of various coal related products can be developed by adjusting the reaction thermodynamics electromagnetically in the presence of active hydrogen species.